OBJECTIVE: To evaluate, in critically ill adults, factors associated with impaired sympathovagal balance. DESIGN: One-month inception cohort study. SETTING: Twenty-six-bed medical intensive care unit of a teaching hospital. PATIENTS: Critically ill adults with an expected duration of intensive care unit stay of > or =48 hrs were enrolled. Patients with permanent arrhythmia or cardiac pacing were not included. INTERVENTIONS: None. MEASUREMENT AND MAIN RESULTS: Sympathovagal balance was assessed on the day after intensive care unit admission by the low-frequency/high-frequency ratio obtained from spectral components of heart rate signal: overall variability, low frequency, and high frequency. RESULTS: Forty-one patients, 13 with sepsis and 28 without sepsis, were assessed. Predictors of low-frequency/high-frequency ratio with the automatic interaction detection method were sepsis and age. Binary logit analysis adjusted for age showed that sepsis remained a strong and independent factor of a low-frequency/high-frequency ratio of <1.50, with an odds ratio of 3.63 (95% confidence interval, 1.47-9.01, p =.005). Use of mechanical ventilation, catecholamines, or sedation did not add any information. The use of the low-frequency/high-frequency ratio in diagnosing sepsis may be supported by a likelihood ratio for low frequency/high frequency <1 at 6.47. CONCLUSIONS: This work suggests that impaired cardiac variability and notably sympathovagal balance (i.e., a low-frequency/high-frequency ratio <1.0) may be a diagnostic test for sepsis.
OBJECTIVE: To evaluate, in critically ill adults, factors associated with impaired sympathovagal balance. DESIGN: One-month inception cohort study. SETTING: Twenty-six-bed medical intensive care unit of a teaching hospital. PATIENTS: Critically ill adults with an expected duration of intensive care unit stay of > or =48 hrs were enrolled. Patients with permanent arrhythmia or cardiac pacing were not included. INTERVENTIONS: None. MEASUREMENT AND MAIN RESULTS: Sympathovagal balance was assessed on the day after intensive care unit admission by the low-frequency/high-frequency ratio obtained from spectral components of heart rate signal: overall variability, low frequency, and high frequency. RESULTS: Forty-one patients, 13 with sepsis and 28 without sepsis, were assessed. Predictors of low-frequency/high-frequency ratio with the automatic interaction detection method were sepsis and age. Binary logit analysis adjusted for age showed that sepsis remained a strong and independent factor of a low-frequency/high-frequency ratio of <1.50, with an odds ratio of 3.63 (95% confidence interval, 1.47-9.01, p =.005). Use of mechanical ventilation, catecholamines, or sedation did not add any information. The use of the low-frequency/high-frequency ratio in diagnosing sepsis may be supported by a likelihood ratio for low frequency/high frequency <1 at 6.47. CONCLUSIONS: This work suggests that impaired cardiac variability and notably sympathovagal balance (i.e., a low-frequency/high-frequency ratio <1.0) may be a diagnostic test for sepsis.
Authors: Jeremy D Scheff; Benjamin Griffel; Siobhan A Corbett; Steve E Calvano; Ioannis P Androulakis Journal: Math Biosci Date: 2014-03-26 Impact factor: 2.144
Authors: Saif Ahmad; Tim Ramsay; Lothar Huebsch; Sarah Flanagan; Sheryl McDiarmid; Izmail Batkin; Lauralyn McIntyre; Sudhir R Sundaresan; Donna E Maziak; Farid M Shamji; Paul Hebert; Dean Fergusson; Alan Tinmouth; Andrew J E Seely Journal: PLoS One Date: 2009-08-14 Impact factor: 3.240